The present invention relates generally to time-indicating devices and particularly to a device for determining the time of another place on the earth from any reference point of which the time is already known.
Over the years, various types of devices have been invented for the determination of time. Some of these devices were adapted to give the time locally, while others would give the time in selected time zones and cities throughout the United States and the world. These devices typically included a dial with specific locations listed in the face of the dial.
However, in order for many of the designs of the latter type, to provide enough reference points to be useful, they were often complicated and difficult to use. This, in part, was brought about by the large amount of writing and figures on the dial. In other instances, where the space on the face was severely limited, only a small number of reference points could be listed without reducing the face to an unreadable display of characters. Thus, the number of locations on the face would in most cases be restricted to the more highly populated and principal areas of the country. In order for the time device to be of general use, this limitation was undesirable, since the listing would not be all inclusive and, many times, the time for a needed geographical location not listed would be needed.
Thus, there is a need for a device which is adapted to give the time of nearly any location on the earth without being unduly confusing.
Many of the prior art devices included a clock movement for moving a pair of hands around a circular face for indicating the time at selected time zones and cities. However, in many instances a time device using a clock movement is not desirable, since the functioning of the time device is dependent upon the proper working of the clock movement. Further, the versatility of the time device is reduced, if the clock movement is electrically operated, since a source of power would be needed to operate the time device. On the other hand, if the clock movement is spring operated, the spring would require periodic winding to prevent the clock mechanism from running down. This generally is not desirable.
Therefore, there is a need for a time device capable of giving the time of any location on the earth without requiring complex mechanical or electrical features.
In some instances, the prior art time devices have not been suitable for use as a teaching aid in educational institutions, because of their complexity. Therefore, if a time device were to be adapted to give the time of nearly any location on the earth while still permitting use by school-age children, it certainly would be very valuable in the teaching of the concept of world time and perhaps even geography.